The second generation of digital airplanes appeared in the late 1980s, models such as the 747-400 and MD-11 that used a multitude of digital computers requiring frequent software updates. It became necessary for the aircraft industry to formulate a strategy on how to make an airline""s job easier in performing software updates on those newly airplane-loadable computers. Flight Management Computers (FMCs) were initially the first to have periodic software updates performed, and those were done according to the Tape Loading standard (ARINC 603) which called for the use of a portable device with one ARINC 429 output and two inputs. The loading was performed by attaching a cable and portable tape loader to the 32-pin data loader connector located in various locations in the cockpit (depending on aircraft type)xe2x80x94either closets on the 757/767 classic airplanes or side panels on the 737 classics near the co-pilot""s station. These were mounted to avoid having the mechanic crawl around in the EE bay every time he was required to perform a software update.
The avionics industry soon realized that portable tape loaders were slow, large and cumbersome and that a new ARINC data loading standard had to developed to accommodate the 3.5xe2x80x3 1.4 Mb floppy disk, which was the most commonly used storage media in the late ""80s. The ARINC 615-1 standard was subsequently approved and released around 1987. The 32-pin connector definition in the original ARINC 603 specification almost doubled to 53 for the new ARINC 615-1 loaders. Some airlines were even demanding that these loaders be configured for permanent mounting on primarily long haul aircraft such as the 747-400. The specification quickly migrated to the -2 and -3 versions in an attempt to accommodate some of these requirements. The specification went from two ARINC 429 output busses and four inputs in 615-2 to four outputs and eight inputs in 615-3, in an attempt to anticipate the maximum number of loadable boxes requiring an interface with the 615 loader. In 1990 eight inputs were enough; however at the present time, there are as many as 24 loadable LRUs on a single aircraft model type.
Aircraft manufacturer Boeing soon realized that the ARINC 615-3 specification would fall short in handling more than eight loadable boxes. At Boeing, a production solution was developed specific to each aircraft model type to accommodate the number of loadable systems, which varied greatly at the time from model to model. Boeing was still selling a lot of 737 classics, and many of those models required only FMC updates. Typical data loader interface configurations consisted of Portable Data Loader (PDL) connectors in various locations in the cockpit, 6 position, 12 position, 20 position, 24 position and 20/4 position rotary switches being offered across the fleet. Finally by 1996, Boeing decided to take a common approach across all models except the 777, which does not use the ARINC 615-3 standard for loading, and make a 20/3 position data loader rotary switch interface basic and stable. The discontinuance of the 737 classic line and the offering of the new generation 737s caused the addition of over 12 loadable LRUs, with more on the horizon. Hence, all Boeing aircraft delivered after March of 1998 could justify the use the cross model switch. There are approximately 200 wires (ARINC 429 in/out, loader enable discretes, function discretes) populating 4 circular connectors located on the data loader switch module assembly installed on the P-61 maintenance panel for the 737/757/767 models and the P-11 panel for the 747. All loadable systems on Boeing airplane models (except the 777) interface with the rotary switch.
As stated previously, the switch interface unit bridges the gap between interfacing with existing avionics systems for data uploading and data acquisition without drastically modifying the way airplanes are currently built (primarily but not limited to Boeing). It""s functionality is easily adaptable so that it can become an integral component on future on-board network systems such as the Aircraft Data Services Link (ADSL). This invention provides marked improvement and capability (when used as the directed data query and download engine to a ARINC 763-type Network Server System such as the ADSL) over the Ground Data Link (GDL) system referenced in U.S. Pat. No. 6,047,165 etc. It allows the ADSL to establish ARINC 615 communication with a multitude of computers, but not limited to the Digital Flight Data Acquisition Unit (DFDAU) and FMC without manual intervention via a selection on the rotary switchxe2x80x94a feature that the GDL does not claim to embody, since that system is specifically a real-time flight performance data capture tool by way of one of the DFDAU""s serial ARINC 573 outputs or a hard wired data loader tool paralleled downstream of the existing rotary switch. This invention allows a drastically different approach to the way that previous inventions acquires and wirelessly relays data to/from the aircraft and ground stations.
This invention used in its ADSL application cannot support real-time flight performance data capture, store and transmit, however upon touchdown, an active query of all the previous flight""s pre-processed ACMS triggered reports, SAR, QAR and DAR historical data along with any other 615 download data, can be initiated by way of the remotely selectable ARINC 429 data loader interfaces connected to this invention. In reality, no accumulated data is lost, and the ADSL cannot be identified as performing a xe2x80x9cnon-confidential real time monitoringxe2x80x9d task, since by virtue of avionics system interlocks in the air, this invention in its ADSL application cannot direct an active query to a loadable system and obtain a response.